For example, when a user requests data, which is not held in a wireless communication terminal provided on a car, the wireless communication terminal connects, for example, to a base station provided in advance via a telephone line, and acquires the requested data from a server connected to the base station. In such a case, because the communication fee occurs every time the terminal connects to the base station, the cost is problem.
By the way, JP-A-H9-252277 discloses a technique for efficiently and broadly delivering local information by carrying out communication typically carried out by a parent station by child stations. In this publication, mobile stations A to D equipped with a relay station deliver information transmitted by a fixed station according to a following procedure. That is, firstly, the information transmitted from the fixed station is received at the mobile station A, and is processed at the mobile station A according to a transmission side algorithm and a receipt side algorithm, and then is relayed to the mobile station B. After that, the information is relayed one by one from the mobile station B to D via C. By relaying the information in such a manner, the information can be broadly communicated by a small power. In addition, it is also possible to make the distribution area of the information local by defining the upper limit of the resending. Thus, because of the small power communication, a problem such as interference to undesired area, which is caused by the large power communication, can be prevented. However, there is no apparent description for how to properly use the short distance communication means and the long distance communication means and what processing is carried out for an information request occurred in a specific mobile station.
In addition, JP-A-H10-32538 discloses a mobile communication method capable of forming a pseudo-network without any wide range communication means, and reducing the system price and effectively using radio waves. More specifically, each mobile object is equipped with a mobile station having a weak radio wave receiving apparatus RX1 and a weak radio wave transmitting apparatus TX1, which can communicate only with neighboring objects, and a traffic information message received from the mobile station of the neighboring mobile object is relayed to mobile stations of other neighboring mobile objects and the traffic information message MS1 to be transmitted by itself is transmitted to mobile stations of other neighboring mobile objects. Or, each mobile object or fixed station is equipped with the weak radio wave receiving apparatus RX1 and the weak radio wave transmitting apparatus TX1, which can communicate only with neighboring objects, and information received from the mobile station of the neighboring mobile object or the fixed station is temporarily stored in a memory MM1, and necessary information is displayed on a display device DS1, and when other neighboring mobile object or fixed station appears, the stored information is resent. Also in this publication, there is no apparent description for how to properly use the short distance communication means and the long distance communication means and what processing is carried out for an information request occurred in a specific mobile station.
Furthermore, U.S. Pat. No. 6,477,353 discloses a technique for propagating information transmitted from an information source by hopping it between mobile stations. More specifically, the mobile station controls so as not to spread the information from the position of the information source by a predetermined distance or more, so as to spread the information only within a valid period when defining the valid period of the information, and so as not to repeat the delivery route and bypass the route. Especially, when the density of the mobile stations becomes high, the information to be transferred should be selected or limited, because the volume of the information to be transferred is explosively increased. When the mobile station is an information mobile terminal and individual users have the information mobile terminals, the information source is a retail store and transmits sales information and the like with the position information, for example. The user who holds the information mobile terminal looks at the sales information, and may go to the sales place or go out of the store if he or she has no interest. When the user goes out of the store and walks, the information mobile terminal held by another user exchanges the information with the information mobile terminal held by the user who was in the store. By repeating this processing, the sales information reaches an individual who has an interest in the sales information. However, there is no apparent description for how to properly use the short distance communication means and the long distance communication means and what processing is carried out for an information request occurred in a specific mobile station.
Furthermore, U.S. Pat. No. 6,574,453 discloses a method including, in a wireless transceiver of a receiving side, a step of measuring a electric field strength of a wireless signal received from another wireless transceiver; and a step of determining a response timing to the received wireless signal based on the measured electric field strength and, for example, a response policy concerning the electric field strength. In addition, the method further includes, in a wireless transceiver of a transmitting side, a step of designating the response policy concerning the electric field strength in the wireless transceiver that receives the wireless signal; and a step of transmitting the wireless signal including the designated response policy to the wireless transceiver. Thus, it becomes possible to designate the wireless transceiver, which exists in a region with which the wireless transceiver of the transmitting side desires to connect. However, there is no apparent description for how to properly use the short distance communication means and the long distance communication means.
In addition, JP-A-2004-106801 discloses a technique to improve traveling safety of a vehicle by enabling a codeless and hands-free call in the driving. Specifically, an information communication system has two main body apparatus side BT modules equipped in the main body; a call device side BT module that corresponds to one main body apparatus side BT module and is equipped in a mobile phone; and a call device side BT module that corresponds to the other main body apparatus side BT module and is equipped in a headset. The two main body apparatus side BT modules are set as a master, and the call device side BT modules are set as a slave against the master. The main body apparatus and the mobile phone are equipped in the vehicle, and the headset and the main body apparatus are positioned within a predetermined distance. Although an apparatus having the long distance communication means and the short distance communication means is disclosed, the spread of the information by the communication between such apparatuses is not considered so much.
Furthermore, JP-A-2003-110751 discloses a portable information apparatus and the like having a wireless telephone function and realizing low-cost and high-speed transfer wireless communication. More specifically, a portable phone is configured so that either a wireless telephone line or wireless communication is selectively used by switching, and it is possible to prohibit the receipt of the data transmitted via the wireless telephone line and/or to carry out a setting so that the wireless LAN line is preferentially used in the data transmission. In a case where the wireless LAN line is used when the communication with any information apparatus on the in-house dedicated line is carried out, the communication fee is reduced by using the company side system. In addition, because the kind of media, which intervene in the data transfer, is a little, high transfer speed is realized. Although the use method of the simple communication means based on the speed, the cost and/or the like is disclosed, there is no consideration for the information propagation by using the communication between the portable information apparatuses.
In addition, JP-A-2002-368757 discloses a delivery control method and the like in a multicast delivery service, in which data delivered in the past can be used in a wireless terminal, the prevention of data missing, which is caused by changes of radio wave propagation condition and lack of wireless resources, can be carried out, and further the charging for the information delivery used by the user can be carried out. Specifically, in an information delivery control method in a multicast delivery service, for delivering multicast information to a specific large number of wireless terminals in a service area via a wireless section from an information delivery apparatus, the wireless terminal accumulates multicast information delivered from the information delivery apparatus in advance, and notifies the information delivery apparatus of identification information to identify the accumulated multicast information at a timing determined by the wireless terminal, and the information delivery apparatus selects the multicast information based on the identification information notified by the wireless terminal, and delivers the selected multicast information to the wireless terminal. This technique is described for the multicast, namely for the communication of one to many, and data propagation between the wireless terminals is not considered.
The conventional techniques do not disclose a technique to efficiently carry out data communication between mobile wireless communication terminals having short distance communication means and long distance communication means.